Various impressions are frequently encountered at crime scenes and are of great importance to law enforcement officials. Impressions can include fingerprints, bloody fingerprints, hand prints, palm prints, foot prints, footwear prints, etc. Other than blood, proteinaceous impressions can include sebaceous, eccrine, saliva, semen, and vaginal secretions. Therefore, developing impressions and bloody proteinaceous impressions on various surfaces is of great interest to the forensic science community. Every finger and palm print, for example, has a series of elevated patterns known as friction ridges which are unique to each individual in the population. As a result, if friction ridges can be visualized in blood, they can be used for identification purposes.
When bloody impressions are located on light-colored surfaces they may be photographed directly, which may provide some visualization of the ridge structure. But when bloody impressions are located on dark colored surfaces there is usually not enough contrast between the bloody impression and the surface to visualize any ridge structure in the impression. Currently, there are a variety of techniques for enhancing bloody impressions on some non-porous, semi-porous and porous surfaces of varying contrasts, yet they are limited in their effectiveness (Caldwell and Kim 2002; Forsythe-Erman 2001; McCarthy and Grieve 1988; Sears and Prizeman 2000; Sears and others 2001; Sears and others 2005; Yapping and Yue 2004). These processes require using chemical reagents and are normally conducted in a laboratory setting, which may be both inconvenient and time consuming. Furthermore, immovable or bulky objects from crime scenes cannot be brought back to the laboratory for analysis. Many potentially identifiable impressions may only be photographed and not enhanced due to limitations of this nature; and this is not in the best interest of society.
Accordingly, the inventor has seen a need for technology that permits law enforcement officials to lift a bloody impression from a crime-scene surface, and to preserve it for further analysis and use. The inventor has also discovered that certain embodiments of the invention are also useful for lifting, preserving, and analyzing prints such as latent fingerprints because these embodiments produce an impression that has fluorescent characteristics when analyzed under certain light sources.